The Oak Bluffs side of Sengekontacket Pond will be closed to recreational and commercial bay scalloping for the 2015-2016 season, shellfish constable David Grunden told the town selectmen Tuesday night. The reason is to protect a heavy set of seed scallops.

Mr. Grunden said recent test dragging netted almost no bay scallops of harvest size from the Oak Bluffs side of the pond.

“We quickly came to the realization that 90 to 95 per cent were seed, some of them large enough to look like adults,” Mr. Grunden said. “To protect the seed from being beat up with drags, or walked across, or being mistaken for adults and brought in, I made the decision to close the pond to scalloping.”

He said the town shellfish committee backed the decision.

“The decision wasn’t easy, I’ll tell you that,” Mr. Grunden said. "I don’t take it lightly.”

For now, the Edgartown side of the popular salt pond will remain open to recreational scallopers, although shellfish constable Paul Bagnall said he plans to re-evaluate the situation later this week. Edgartown allows only recreational scalloping in Sengekontacket, also called Anthier’s Pond on the Edgartown side of the bay.

Recreational scalloping opened in all Edgartown ponds on Oct. 1. Commercial scalloping begins Nov. 2. In Oak Bluffs the recreational season opens Saturday in Vineyard Haven outer harbor and Nantucket Sound. Commercial scalloping begins there Oct. 26. In Lagoon Pond, recreational scalloping begins Oct. 31, and the commercial season starts Nov. 2.

The reason for the unusual conditions in Sengekontacket this year is anyone’s guess, shellfish wardens in both towns said. It could be environmental factors, or it might be just unlucky circumstances.

“Mother Nature is most of what it is,” Mr. Grunden said. “This is something I’ve never seen before.”

“That’s the million-dollar question,” Mr. Bagnall agreed.

Mr. Bagnall said the Edgartown side of the pond is not nearly as heavily fished as the Oak Bluffs side.

“We’re still evaluating our side. There are a few adults,” Mr. Bagnall said. “There are only one or two dip netters a day. We don’t allow dragging on our side.”

There may be a silver lining: the harvest may be more abundant next year.

“If Mother Nature cooperates it could be a real good season in Sengekontacket,” Mr. Grunden said. “We’ll have to see what kind of winter we get.”

In a separate development, Oak Bluffs selectmen approved new oyster fishing regulations for Sengekontacket Pond, though oysters from a new propagation program in Sengekontacket Pond will not be ready for harvest until next fall.

Recreational shellfish permit holders will be allowed to take a half-bushel of oysters, in addition to their current limit of a half-bushel of quahaugs or other shellfish.

The town wants to encourage a substantial harvest, because oysters remove nitrogen from the water. The oyster season will run from Nov. 1 to April 1, avoiding the higher water temperatures of summer, when shellfish are more susceptible to bacterial contamination.

“We’re doing this to avoid any of the vibrio contamination,” Mr. Grunden said.

A total of 250,000 seed oysters were distributed in the area of Major’s Cove over the past year.